This systematic review and meta-analysis found that 360-degree selective laser trabeculoplasty (SLT) is significantly more effective than 180-degree SLT at reducing intraocular pressure at 1-month and 1-year follow-ups without increased serious adverse event risk. To determine the efficacy of 180- versus 360-degree selective laser trabeculoplasty (SLT) in adults with open angle glaucoma (OAG) and ocular hypertension (OHT). A systematic review was performed using PubMed, Embase, and Scopus databases, from 1995 to December 30, 2023, for studies comparing 180 and 360-degree SLT in adults with OAG and OHT (PROSPERO ID: CRD42024497832). Meta-analyses were performed to calculate nominal percent and raw reductions in intraocular pressure (IOP) between treatment groups at 1-month, 1-year, and 2-year follow-ups, as well as success rates, defined as a 20% or greater IOP reduction. Nine studies with 1044 eyes were included; 491 received 180-degree SLT, and 553 received 360-degree SLT. At the 1-month follow-up, 360-degree SLT reduced IOP by 3.45% more (WMD=3.45; 95% CI: 2.02-4.88; P <0.00001) and 0.87mmHg more (WMD=0.87; 95% CI: 0.35-1.38; P =0.0010). At the 1-year follow-up, 360-degree SLT reduced IOP by 4.33% more (WMD=4.33; 95% CI: 2.35-6.32; P <0.0001) and 1.15mmHg more (WMD=1.15; 95% CI: 0.25-2.04; P =0.01). At 2 years of follow-up, 360-degree SLT reduced IOP by 4.86% more (WMD=4.86; 95% CI: -0.32, 10.0; P =0.07) and 1.25mmHg more (WMD=1.25; 95% CI: -0.29, 2.79; P =0.11); however, the difference was not statistically significant. Compared with 360-degree SLT, 180-degree SLT had a significantly lower success rate (OR=0.50; 95% CI: 0.35-0.72; P =0.0002). There was no difference in serious complications between interventions. 360-degree SLT is more effective than 180-degree SLT at lowering IOP at 1-month and 1-year follow-ups as well as achieving successful IOP control without increased risk of serious complications.